Wine typically diminishes in quality and freshness relatively quickly after a bottle is initially opened. The quality and freshness of wine in an opened bottle may begin decreasing within several hours of the bottle being opened and may continue to decrease to an unacceptable level within several days. Many factors may contribute to how quickly an opened bottle of wine degrades. These factors can include storage conditions, number of times the bottle is opened, how quickly the bottle is resealed, the initial quality of the wine, the type of wine, the age of the wine, and the pH of the wine, as well as other factors, including combinations thereof. Because there are potentially multiple factors that can contribute to the degradation of the wine, it can be difficult to precisely predict when an opened bottle of wine has progressed to an unacceptable level of freshness or quality because a simple measure of time since the bottle has been opened may be insufficient in some circumstances.
In bars, restaurants, and other commercial establishments that serve wine, monitoring wine quality may be a particular challenge due to the relatively large number of open bottles that may be on hand and the period of time that may pass between successive servings from each open bottle. Due to the cost of wine, establishments cannot afford to prematurely discard opened bottles due to mere suspicion that a wine may no longer be good. At the same time, serving wine that has degraded beyond a good or acceptable level can also have negative impacts on the establishment due to customer dissatisfaction and/or impacts on reputation. Consequently, there is a need for improved methods of determining and monitoring freshness of wine stored in a container.